My Keurig B70 has begun dispersing various amounts of water no matter what size cup is chosen

The Keurig machine operates by pumping air into the glass boiler to drive the hot water through your coffee cartridge. When you have put a new cartridge into the dispenser, you select a size of cup. When you press the go button, you should hear the machine pump water into the boiler to the requested cup size (test by selecting large size to hear the pumping work). Next the machine operates an air pump to force the specific amount of hot water through the cartridge and make the cup of coffee. The problem encountered with these machine is that a small amount of water can drip internally onto the air pump and it will either not operate or work intermittantly. There is a great 'how to fix' video on utube concerning the Keurig-taking apart and fixing.
Honestly, I don't know whether this is your problem, but I do know this happened to a machine I had. You should hear the tiny air pump working when the cup of coffee should be brewing. You can laboriously take apart and replace, and given the price of these units it may be practicle to do the repair. Watch video on utube--its like three or four parts and very instructive. Sorry I don't have the link.

Reset to Factory condition and purge system.

Hi,

Here is a tip that I wrote that will give you some things to try that will helpyou get your Keurig coffee brewer workingagain.

Keurig CoffeeBrewer not making a full cup of Coffee
heatman101

Hi,

Here is a tip that I wrote that will give you some things to try that will helpyou get your Keurig coffee brewer workingagain.

Keurig CoffeeBrewer not making a full cup of Coffee
heatman101

=-=-

Hi,

Here is a tip that I wrote that will give you some things to try that will helpyou get your Keurig coffee brewer workingagain.

Keurig CoffeeBrewer not making a full cup of Coffee
heatman101

Hi,

Here is a tip that I wrote that will give you some things to try that will helpyou get your Keurig coffee brewer workingagain.

Keurig CoffeeBrewer not making a full cup of Coffee
heatman101

';';

Hi,

Here is a tip that I wrote that will give you some things to try that will helpyou get your Keurig coffee brewer workingagain.

Keurig CoffeeBrewer not making a full cup of Coffee
heatman101

Hi,

Here is a tip that I wrote that will give you some things to try that will helpyou get your Keurig coffee brewer workingagain.

Keurig CoffeeBrewer not making a full cup of Coffee
heatman101

Hi,

Here is a tip that I wrote that will give you some things to try that will help you get your Keurig coffee brewer working again.

Keurig Coffee Brewer not making a full cup of Coffee

heatman101

';][

If you can also see there are a lot of inquiries about the same or similar problem. We have already investigate the matter and it is a design problem from Keurig and it not any much that you can do,
We have a tip at the link that it explains it some more
http://www.fixya.com/support/r5543433-keuring_coffee_maker_b60_b70

Moreover you can contact the keurig customer service which we here that they are more than happy to help you and in many cases they have replace the machines with no further question, you can try also since you are a customer with rights.
Good luck